We describe a parameterized reduction from Clique. In Clique one is given an undirected graph \(G\)  together with an integer \(k\)  and the question is if \(G\)  contains a clique of size \(k\) , that is, a set of pairwise adjacent vertices. Clique is \(\mathrm {W}[1]\) -hard when parameterized by \(k\)  [1]}.
